There is a growing interest in reducing the power consumption of electronic devices, such as hard disk drive systems. For example, if a hard disk drive system operates off a battery, the battery life can be extended by reducing power consumption. Even in the case of an AC power supply, consumers are becoming increasingly aware about power consumption and the natural resources (such as coal or oil) that are consumed to generate that power. It would be desirable if techniques for saving power in hard disk drive systems could be developed.